Internal Error: Sub-system: VPR20KMAIN, File: /quartus/fitter/vpr20k/nf_arch/nf_net_rr_terminals.c, Line: 507 - Internal Error: Sub-system: VPR20KMAIN, File: /quartus/fitter/vpr20k/nf_arch/nf_net_rr_terminals.c, Line: 507 Description Due to a problem in the Intel® Quartus® Prime Pro Edition software version 17.1 and earlier, you may see this internal error at Fitter stage for design targeting Intel Arria® 10 devices. Resolution This problem is fixed begining with the Intel Quartus Prime Pro Edition software version 17.1 Update 1 Custom Fields values: ['novalue'] Troubleshooting FB: 520901; False ['novalue'] ['FPGA Dev Tools Quartus® Prime Software Pro'] 17.1.1 17.1 ['Arria® 10 FPGAs and SoCs'] ['novalue'] ['novalue'] ['novalue']